Machine for folding blanks



Oct. 28, 1941.

F. H. CHAPMAN MACHINE FOR FOLDING BLANKS Filed Aug. 20, 1940 5Sheets-Sheet l INVENTOR. FTEE] H Ehapn gj BY W%M ATTORNEY.

Oct. 28,.1941. F. H. CHAPMAN MACHINE FOR FOLDING BLANKS Filed Aug. 20,'1940 5 Sheets-Sheet 2 INVENTOR vVll/ll 7 6 l FfE d' H Chapman BYATTORNEY Oct. 28, 1941. F. H. CHAPMAN MACHINE FORFQLDING BLANKS FiledAug. 20, .1940 5 Sheets-Sheet 5 5 J. Rt m o WW m M w A V.. B.

1941- F. H. CHAPMAN MACHINE FOR FOLDING BLANKS Filed Aug. 20, 1940 5Sheets -Sheet 4 l -JE INVENTOR. FF'Ed H Chapman IQMA ATTORNEY.

Oct. 28, 1941. HCHAPMAN 2,261,018

MACHINE FOR FOLDING BLANKS v Filec l Aug. 20, 1940 5 Sheets-Sheet 5 'iq-9 5.5-.

(1J1? b x l I I l I I t I I l I i L 6/: .9 I E l J I Y I i I l f I f-"INVENTOR- l r'ed H Chapman BY WWW ATTORNEY Patented Oct. 28, 1941 MAcmNnoR FOLDINGBLANKS 'Fred H. Chapman, Pcpper ell, Mass., assignor to TheInternational Paper Box Machine Company, Nashua, N. H

Hampshire a corporation of New Application August 20, 1949, Serial No.353,374

' '9 Claims. (01. 93-49) This invention relates to machines for folding.blanks.

In the manufacture [of boxes and generally .similar articles frompaperboard, boxboard or similar sheet material, it is necessary to makeIt is usually desircertain folds in the blank. I able that the folds bemade while theblank is traveling in order to provide a highrateofprbduction. It has been found relatively difiicult main body ofthe blank and the side wall flaps. In accordance with the presentinvention, a folding mechanism is provided wherein a relatively simplebut positively acting and eflicient mechsuch construction that itengages the portions of the blank other than the portions to be fold-.ed. A rotatable folding arm carrying an angularly yielding head isrotated to engage a rearward flap of the blank and fold it forwardlyover against the body of the blank; when the fold is substantially made,the head is rocked away from the blank to allow the latter to beadvanced by the conveyor. made, a second folding head is-rota-tedsomewhat in advance of the rearward folding head and engages and turns aforward flap or .flaps rearwardly. Suitable means, such as folder bars,are provided for completing the folds.

An object of the present invention is the provision of a simple andeflicient mechanism for making diagonal folds in blanks while they aretraveling. I I

Still another object of theinvention is the provision of a simple andefficient mechanism for folding forwardly a trailing flap of a blankwhile the blank is being advanced through the mechanism. I

Still another object of the invention is the provision of a simple andefiicient mechanism .2 .of the invention, the blanks are suitablyadvanced through the mechanism by a conveyor of Where a front fold is tobe to make the so-called diagonal folds wherein the 10 .blank is foldedalong fold lines makingan acute angle with the lines of juncture betweenthe lieved to be characteristic of this invention will be. particularlypointed out in the claims appended hereto, the invention'itself, as toits objectsand advantages, and the mannerin which it may be carried out,may be better understood by referring to the following description takeni n con necti on with the accompanying drawings forming a part hereof,in which Figs, 1 and 2 are fragmentary vtop plan and side elevationalviews respectively, showing a -portion of a folding mechanismconstructed in accordance with the present invention; 7

Figs, 3 and dare fragmentary top plan and side elevational viewsrespectively, illustrating particularly the folding of a forward flapbackwardly onto the body of the blank, certain parts pf thestructurebeing omitted to simplify the sh w n Figs, 5 and 6 are fragmentary topplan and side elevational views respectively, illustrating particularlythe folding of a rear flap forward- ;ly, certain parts being omitted forsimplicity;

Figs. '7 and 8 are top plan and side elevational views respectively ofanother embodiment of the invention and representing a portion of amechanism for folding forwardly a rear center flap having diagonal foldstherein, certain parts of the structure being omitted for simplicity;

.Fig. 9 is a top plan viewof one'fo'rm of blank which the mechanismillustrated in Figs. 1 to 6 is adapted to. fold;

Fig. 10 is atop plan view of the blank shown in Fig. 9 after folding"; l

Fig. 11 is a top plan view of one form of blank which the mechanismillustrated in Figs. 7 and 8 is adapted to fold; and

in the several figures of the drawings.

It will be understood that the present invendtion is adapted to manyuses in connection with for making forward and rearward diagonal foldson a blank during the forward movement of the blank.

Various other features and advantages'of the invention will be apparentfrom the following particular description and from an inspection of Ithe accompanying drawings.

Although the novel features which 'are'be- 'pendent machine for merelymaking folds in blanks, will more usually be employed as acomponent partof a machine for foldingand. gluing blanks to make complete boxes. Itwill be understood, therefore, that while a showing of such combinedmachine is omitted for simplicity,the mechanism herein disclosed may becombined with other known folding and/or gluing mechanism to provide acomplete box making ma-v chine.

It will be also understood that while the present invention is primarilydirected to a mechanism for making diagonal folds, nevertheless, themechanism, with certain modifications as hereinafter more fullyexplained, may be employed for making regular folds along fold linesparallel to or at right angles to the direction of movement of theblank.

Before describing the machine it should be noted that it is shown inconnection with two forms of blank having diagonal fold lines therein.

One form of blank is illustrated in Fig. 9, to which reference now ismade. The blank L includes a base at having side walls I; foldable alongfold lines and end walls 11 foldable along fold line e. The end walls dhave diagonal corner flaps extending therefrom and foldable about thefold lines 9.

Referring now particularly to Fig. 1, there is shown in a somewhatdiagrammatic manner, a mechanism for folding blanks. The mechanism isadapted to be mounted on a suitable frame (not shown) which may be theprincipal frame on the machine. Inasmuch as the two side portions of themachine are similar, only one such portion is described herein, it beingunderstood that the other is similar but reversed, in order to provideright hand and left hand portions; the right hand portion is illustratedherein.

Extending longitudinally of the mechanism are supporting bars Ill and IIwhich serve to support the blank thereon. Any suitable means may beprovided for advancing the blank but for purposes of illustration thereis shown upper and lower belts I2 and I5, which are trained aroundsuitable pulleys (not shown) and are suitably driven.

Supporting rolls |3 rotatably mounted in a lower bracket M are disposedunder the lower belt l2. Upper presser rolls l6, carried in carriagesI1, bear against the upper belt l5 and press it against the lower beltl2. Each of the carriages l1 supports two rollers and is mounted forvertical movement by a rod l8 extending through a block l9 adjustablymounted on a bracket 29. Compression springs 6| resiliently urge thecarriage downwardly to yieldingly press the rolls l5 against the upperbelt I5.

Top bar 62 (see Figs. 3 and 4) is provided for resisting the foldingpressure of the forward flap, as will be explained more fullyhereinafter. A second top bar 2| (see Figs. 1 and 2) is provided forresisting the folding pressure on the rearward flap.

A curved folder bar 22 is provided for folding down the forward flap andretaining the fold of the rearward flaps, after the forward flap hasbeen initially raised and partially folded and the rearward flap hasbeen folded.

A rotating folder is mounted adjacent the path of :the blank andincludes a rear flap folder and, where desired, also a forward flapfolder.

A sleeve 25 is mounted on a shaft 25 which is rotated by suitable means(not shown) in timed relation to the movement of the blanks. The forwardflap folder arm 21 is carried by a hub 28 rigidly secured to the sleeve25 by a clamp .29 which permits angular adjustment of the arm 21 on thesleeve 25. A head 3| of suitable .shape is carried by a shank 30 whichis adjustably secured as by a bolt 63 to the arm 21.

In the present case the head 3| is of generally trapesoidal shape withits forward and rearward edges 64 and 65 converging inwardly to avoidthe inner side edge 66, as illustrated particularly in Fig. 3.

The rearward flap folder arm 35 is carried by a hub 36 rigidly securedto the sleeve 25 by a clamp 31 which permits angular adjustment of thearm 35 on the sleeve 25. Pivotally carried at the end of the arm 35 asby a pivot pin 38 is an extension 39 carrying a head 44 which isadjustable on the extension as by a bolt 45. The extension 39 isnormally urged in a clockwise direction relative to its pivot by aspring 42 hearing against the arm 35 and against one or more nuts 43threaded on a stud 40 which stud 40 is pivotally connected to theextension 39 as by a pin 4|.

The extension 39 carries a cam follower 50 adapted to strike against acam 5| when the arm 35 is rotated and rotate the extension 39 about itspivot in a counter-clockwise direction for a purpose hereinafterdescribed. The cam 5| has a suitably shaped surface 52 for efiectingthis rocking of the extension 39. The lower portion of thebar may be cutaway or indicated at 53 to permit the follower 5|) to pass under it. p 3

The operation of the mechanism thus far described is as follows:

The blank L is advanced by the conveyor, and the rotating folder isrotated in suitably timed relation to the movement of the blank. Thespeed of rotation is such that the folder heads 3| and 44 have aslightly greater lineal speed than the blank. V

The forward flap folder head 3| engages "the forward corner flap f andraises it prior to the time that the blank reaches the folder portion ofthe folder and fold retaining bar 22. As the blank continues forward,the forward corner flap 1 is engaged successively by the forward edge54, the inner edge 66 and the rearward edge 65 of the forward folderhead 3| and finally is engaged by the folder bar 22 which folds thecorner flap rearward and downwardly against the body of the blank asillustrated particularly in Fig. l of the drawings. Owing to the shapeof the head 3|, the flap is raised and folded about the 45 diagonal foldline g. The head 3| is shown with a double face of approximately 45 sothat it may be used at either side of the machine.

The top bar 62 under which the flap 2) rides restrains this portion ofthe blank against raising when the head 3! engages and lifts the flapand thusprovides folding resistance. The top bar 62 is suitably disposedin advance'of the folder so that the flap f clears the bar before it israised.

The rearward flap folding arm 35 is rotated in following angularrelation with the arm 21 and the head 44 engages the rearward cornerflap f and raises it before it comes opposite the end of the folder bar22. The head '44 is formed with a forward inclined edge which extends ata'45 angle to the direction of the movement ofthe blank and thusmovement ofthis head insures that the folded portion of the blank-isfolded along the 45 diagonal line of fold Q. When the head has turnedthe rearward corner flap f approximately and under the folder bar 22,the follower 50 engages the cam 5| and rocks the head out of engagementwith the blank L and thereby prevents the head 44 from binding orclamping the blank against thegsupporting bars lfla'n'dll;

. shown.

, The top bar -2 I is ipositioned-to' engage the side fia-p b after theforward corner flap f raised and before therearward corner flap 7 israised. This bar 21, in a sense, constitutes a continuation of the .bar62 and serves in ananalo'gous manner to .provide folding resistanceduring the folding of the rear tcornerflap.

The blank L then is advanced away from :the head 44 and the folder .bar22 maintains .the folded front and rear flaps infolded condition.

The blank is then ready for such furtheroperations as may be desired Asecond embodiment of the invention is es- ;pecially Well adaptedforfolding a rear'center flap forwardly and simultaneously making adiagonal fold in such flap. One form shown by the rear portions of ablank W .illustrating this folder operation is shown in Fig. 11 to whichreference bodiment is generally similar to that shown in Figs. '1 to 6,inclusive, and described her-einbefore,

the principal-difference being that the folder arm is positioned toengage the rearwardfiap instead of the corner flap. Also, in theparticular embodiment illustrated, no forward folder arm is employed. I

"The blank is supported on supporting bars II!) and I II and is advancedtherealong by a chain H2 having spaced lugs I'HJ, one of which isThe'lugs are so spaced that each one engages a blank to advance it alongthe supporting fbars' H and III when the chains are suitably driven.

' A top bar I I is provided under which the blank rides and whichresists the folding pressure on the blank as hereinafter explained.

'It will be understood that conveyor means other than that illustratedherein can be employed for advancing the blank. It is important,however, that 'theblank be advanced by means which engages it outside ofthe line of fold of the rear fiap so as not to interfere with thefolding operation. For example, cooperating belts, such as previouslydescribed herein, can be employed instead of the chains.

A shaft 125 mounts a mad arm I35 which pivotally mounts an extension I39generally similar to the extension 39 hereinbefore described. Theextension I39 carries a follower I50 adapted to cooperate with a cam I5Iin a manner generally similar'to the operation described inconnectionwith the previously described embodiment of the invention.

The extension I39 carries ahead I44 which is adjustable on the extensionand which is provide'd'with a forward edge I46 inclined rearwardly "andoutwardly at anangle of approximately 145.

The arm I35 is so mounted that the'head I44 is positionedto engage therear wall flap n of the blank inwardly of the diagonal fold line q, the

"inclined edge being shaped to permit the triangular-portionpto befolded rearwardly-onto the re- .and rear corner i'The-operation- .of thesecond embodiment is as follows: The blank is advanced past the .folder'by the 'lug JIi'IIl, carried by the chain H2, and thelug and chaininotshown) at the other side of'tth'e machine. 1

.Prior to the time :that 'the blank reaches the folder; the irearpornerflap r is raised to a position perpendicular to the plane of theremainder .of the blank by suitable means (not shown). :The :flaprjisheld in elevated position by the :folder bar 12-2..

'The folder 1arm .135 is :rotated at a suitable speed such .xthatthe:lineal velocity of the head I44 is ,greater; than the .velocity of theblank past the folder. The forward edge I46 of the 'headengages therearward flap n and raises it andwthereafter turns it down about thefold .1ine O. .'During the turning down of the rear- "ward wall flap-n,"the rearward corner flap 1 -bears-against the base m and preventsthe triangular corner portion 17 from being lowered;

thus the blank folds about the diagonal score line q. As the rearwardwall flap n is folded downwardly against the base m, the blank iscarried into a. :position wherein the folder bar I22 folds the rearwardcorner flap 1' downwardly and inwardly; the triangular corner portion pis, by this action, folded downwardly and rear- -wardly aboutthediagonal fold line q.

Thus the blank leaves the folder with the rearward wall flap or foldedforwardly against the basem, the triangular corner portion 1) folded .in--a reverse direction against the rearward wall flapn and the rearwardcorner flap 1" folded inwardly'ontothe triangular corner portion p.

During the folding of the rearward wall flap "n, the head I44 is cammedaway from the blank in a manner generally similar to that previously.-described, The oam I5I engages the follower "of the invention, servesto resist the raising of -the;rear :flap as the triangular cornerportion flap r are folded by the folder barIZZ.

While both embodimentsof the invention have been described as beingsimilar but reversed at theright hand and left hand sides of themachine, it will be understoodthat cases where blanks are tobe foldedwhich are not symmetrical with respect to theirright and left handportions, the

mechanism herein described may be employed at.

one side of the blank and some other type of folder mechanism employedat the other side of the blank. Where a foldingmechanism similar to thatshown in either of the present embodiments is employed at both sides ofthe blank, the folding operation preferably is carried outsimultaneously at both right. hand and left hand sides of the blank.

porting members may be employed instead of It willbe understood thatother forms of supthe folder arms for supporting the folder heads;

if desired, a single member may .be supplied for supporting both headsbut the heads should be adjustable thereon.

The rear flap folder head may be attached to :its isupportbysothermeansthan the pivoted arm shown, but it is important that it 'lbeyieldinglyattached in order to permit it to be moved out of engagement with theblank to permit the blank to be advanced after the rear fold has beencompleted.

It has been previously noted that each of the folder arms is angularlyadjustable on its supporting shaft and that each of the heads isadjustable on its supporting arm. Thus, the mechanism lends itselfreadily to various adjustments for operating upon blanks of variousshapes and sizes. Where a shorter blank than that shown is employed, theangular distance between the two folder arms is correspondinglydecreased and where a longer blank is to be folded the angular distanceis increased.

Where the mechanism is to be used for folding relatively short blanks,additional folder arms carrying suitable heads may be mounted ontheshaft so that more than one blank is folded during a single revolutionof the folder. In certain cases moreover, it may be desirable to performmore than'two folding operations on each side of a single blank in whichcase a suitable number of folder heads carried by folder arms isprovided.

The apparatus also is capable of being adjusted readily for operatingupon blanks of varying widths This adjustment is accomplished bylaterally adjusting the folder arms on their supporting shaft andadjusting the lateral positions of the top bars, folder bars andconveyor mechanism.

Where the term box is used herein without qualification, it will beunderstood that this includes either a box or a cover therefor oranalogous structures formed from paperboard or like material. Where theterm side wall or end wall is employed without qualification, it isunderstood that this is merely for convenience and not in limitation,inasmuch as it is well known that the relative dimensions of abox can bevaried and that the-wall that might be considered an end wall in certaincases would, in a box be different dimensions, be considered a sidewall.

While certain novel features of the invention have been disclosedherein, and are pointed out in the annexed claims, it will be understoodthat various omissions, substitutions and changes may be made by thoseskilled in the art without departing from the spirit of the inventionWhat is claimed is:

. 1. A machine for folding blanks along diagonal fold lines including,means for advancing a blank, a rotatably mounted support, a head pivotedto said support and yieldingly maintained in predetermined angularposition relative tosaid support, means for rotating said support toengage said head with a blank to fold a rearward flap forwardly, meansactive to rock said head on said support in a direction opposite thedirection of rotation of said support to disengage said head from saidblank at the completion of the folding of said flap, and means forretaining the fold of said flap.

2. A machine for folding blanks along diagonal fold lines includingmeans for advancing a blank, a rotatably mounted folder member having aportion formed with a blank engaging surface inclined angularly to theplane of rotation of said folder member, means for rotating said foldermember in a plane parallel to the direction of travel of said blank, andmeans for rocking said portion in said plane to clear said blank afterfolding. 1

'3. A machine for folding blanks comprising means for advancing blanks,a rotating folder .arm, a folder head pivotally carried by said arm,

means resiliently positioning said head on said arm, means for rotatingsaid arm, and cam means engageableby said arm during a portion of itsrotation for rocking said head against the resistance of said resilientmeans, and reversely to the direction of rotation of said arm.

4. A machine for folding blanks and the like comprising means foradvancing blanks, a rotatable folder including an arm, a folder headyieldingly carried by said arm, means for rotating said arm to causesaid head to fold a flap of said blank, and means rocking said head onsaid arm reversely to the direction of rotation of said arm to disengagesaid head from said blank.

5. A machine for folding blanks and the like comprising means foradvancing the blanks, a rotatable folder including a first memberengageable with a forward flap to fold it rearwardly and a second memberengageable with a rearward flap to fold it forwardly, and means forrotating said folder at a lineal speed of said members greater than thelineal speed of said blank.

-6. A machine for folding blanks and the like comprising means foradvancing the blanks, a rotatable folder head, means for actuating saidfolder head to lift a rearward portion of the blank from the plane ofthe blank and move said portion forward and over to an arc ofapproximately means for receiving and retaining the fold, and means tocause a rearward yielding of said head at the completion of the fold topermit the blank to move away from said head.

7. A machine for folding blanks and the like comprising means foradvancing the blank, a r0- tatable, yielding folder head, means formoving said head forwardly at a lineal speed greater than the speed ofthe blank, whereby said head contacts a rearward diagonal creasedportion of the blank and turns the same forward on an arc ofapproximately 180, and means to cause a yielding of the head in arearward direction at the completion of the folding of said flap.

8. A machine for folding blanks and the like comprising means foradvancing the blanks, a rotatable folder including a first memberengageable with a forward flap, and a second and yielding memberengageable with a rearward flap, means for rotating said folder at alineal speed of said members greater than the lineal speed of the blank,means for finishing the fold of the forward flap after being raised bysaid first memher, said second member moving the rearward flap forwardon an arc of approximately 180, means for retaining the fold, and meansto cause a yielding of the second member rearwardly before passing belowthe plane of the blank.

9. A machine for folding blanks and the like comprising means foradvancing the blank, 9.

rotatable member, a folder head mounted on said FRED H. CHAPMAN.

